I am wondering as memory management is a responsibility of the kernel and with openvz there is only a single kernel what benefit is there of running 64bit guests over 32bit guests if you are only running 32 bit programs even if they do use a lot of memory?

> Hi,
>
> I am wondering as memory management is a responsibility of the
> kernel and with openvz there is only a single kernel what benefit is
> there of running 64bit guests over 32bit guests if you are only
> running 32 bit programs even if they do use a lot of memory?

In a 64Bit guest (container) the 64 Bit libs are installed, so you can
run 64 Bit and 32 bit applications. With 32Bit guest OS you usally
don't have 64bit libs.

> what benefit is there of running 64bit guests over 32bit guests if you are only running 32 bit programs even if they do use a lot of memory?

I'd say that this kind of depends on expected usage.

On a 64-bit node you can run 32-bit and 64-bit containers, so there is
some flexibility.

For a general purpose run-of-the-mill web- and email server which does a
bit of MySQL and PHP scripting on the sidelines it usually doesn't make
much difference if you use a 32-bit or a 64-bit guest OS in the container.

I use the same OS in 32-bit and 64-bit versions on OpenVZ and typically
see no difference in their performance.

In my experience 64-bit only starts to shine when you have plenty of RAM
and use applications in the guest OS which really make use of 64-bit
stuff. Like massive parallel processing, heavy database usage or
graphics rendering. YMMV.

> Hi,
>
> I am wondering as memory management is a responsibility of the kernel and with openvz there is only a single kernel what benefit is there of running 64bit guests over 32bit guests if you are only running 32 bit programs even if they do use a lot of memory?
>
> Regards
>
> Mark

On 10/09/12 15:00, Mark Olliver wrote:
> Hi,
>
> I am wondering as memory management is a responsibility of the kernel
> and with openvz there is only a single kernel what benefit is there
> of running 64bit guests over 32bit guests if you are only running 32
> bit programs even if they do use a lot of memory?
>

If the host kernel is 64-bit, you can choose 32-bit or 64-bit for the
guests (you can also have a mainly 64-bit guest and run 32-bit apps there).

64-bit has three advantages over 32-bit. It allows easier access to
more memory, the amd64 cpu architecture is somewhat less brain-dead than
the x86 (it has more registers and a more orthogonal instruction set),
and it supports more new instructions (more SIMD code, and instructions
using longer integers).

So if you have code that involves heavy maths, or can benefit from large
amounts of memory, then 64-bit will be a big win.

32-bit has the advantage of using less memory for data structures with
pointers, and being slightly more compact code - both leading to higher
cache hit rates.

Overall, there is seldom a significant performance or size difference
between the two - but 64-bit code has the edge on average.

On the other hand, some software (especially binary-only software) is
only available in 32-bit.

For my own use, I use 64-bit almost everywhere, except in a couple of
containers where 32-bit makes it easier to install the particular
software I wanted on that virtual machine.

just checked it (also with the german version 5.1.1 of IOS) and it works
fine.

greetings,
joe

Am 11.09.2012 15:24, schrieb Christian Blaich:
> Hi,
>
> i would like to check the Backup Status of my Servers after getting up
> on my Iphone/Ipad.
> But unfortunatelly the mail can't be displayed.
>
> The error is the following (got the german IOS):
>
> Diese E-Mail ist so formatiert, dass sie nicht angezeigt werden konnte
> Die E-Mail muss in einem anderen Format oder mit einem anderen
> E-Mail-Programm erneut verschickt werden, multipart/alternative
>
> I think the english error should be like (translated):
> The e-mail is not well formated and can't be displayed. Please resend it
> in a new format or try to change the E-Mail Prog.
>
> Are there any settings to change the output of vzdump mails ?
>
> Greets
> chris
--
Joseph Hauptmann

hm i got an Iphone and Ipad and both don't work.
What excactly did you receive ? Can you forward the Message to me ?

Greets

Am 17.09.2012 10:50, schrieb Joseph Hauptmann:
> hi,
>
> just checked it (also with the german version 5.1.1 of IOS) and it works
> fine.
>
> greetings,
> joe
>
> Am 11.09.2012 15:24, schrieb Christian Blaich:
>> Hi,
>>
>> i would like to check the Backup Status of my Servers after getting up
>> on my Iphone/Ipad.
>> But unfortunatelly the mail can't be displayed.
>>
>> The error is the following (got the german IOS):
>>
>> Diese E-Mail ist so formatiert, dass sie nicht angezeigt werden konnte
>> Die E-Mail muss in einem anderen Format oder mit einem anderen
>> E-Mail-Programm erneut verschickt werden, multipart/alternative
>>
>> I think the english error should be like (translated):
>> The e-mail is not well formated and can't be displayed. Please resend it
>> in a new format or try to change the E-Mail Prog.
>>
>> Are there any settings to change the output of vzdump mails ?
>>
>> Greets
>> chris
--
Gruß
Christian

Interesting, I'm using PVE (Proxmox) and the current Version of vzdump
is 2.1.
It belongs to package pve-manager 2.1-14.

But great to know that it works under packages from Squeeze mirror.
I'll ask in the pve mailing list.

Thx Joe
Greets chris

Am 17.09.2012 17:36, schrieb Joseph Hauptmann:
> i'm afraid not. at least not this week as I'm not going to find time to
> anonymize the sourcecode.
>
> if it's really important to you remind me on friday and I will forward
> you the output during the weekend.
>
> which version are you using? the message I tested on the iphone was
> genereted by vzdump_1.2.6-2_all.deb (MD5sum:
> 272546d428d6dc749ef7621aa9a4ec48).
>
> greetings, joe
>
>
> Am 17.09.2012 16:29, schrieb Christian Blaich:
>> Hi Joe,
>>
>> hm i got an Iphone and Ipad and both don't work.
>> What excactly did you receive ? Can you forward the Message to me ?
>>
>> Greets
>>
>> Am 17.09.2012 10:50, schrieb Joseph Hauptmann:
>>> hi,
>>>
>>> just checked it (also with the german version 5.1.1 of IOS) and it works
>>> fine.
>>>
>>> greetings,
>>> joe
>>>
>>> Am 11.09.2012 15:24, schrieb Christian Blaich:
>>>> Hi,
>>>>
>>>> i would like to check the Backup Status of my Servers after getting up
>>>> on my Iphone/Ipad.
>>>> But unfortunatelly the mail can't be displayed.
>>>>
>>>> The error is the following (got the german IOS):
>>>>
>>>> Diese E-Mail ist so formatiert, dass sie nicht angezeigt werden konnte
>>>> Die E-Mail muss in einem anderen Format oder mit einem anderen
>>>> E-Mail-Programm erneut verschickt werden, multipart/alternative
>>>>
>>>> I think the english error should be like (translated):
>>>> The e-mail is not well formated and can't be displayed. Please resend it
>>>> in a new format or try to change the E-Mail Prog.
>>>>
>>>> Are there any settings to change the output of vzdump mails ?
>>>>
>>>> Greets
>>>> chris
--
Gruß
Christian